The delivery of items typically includes picking and packaging the items, providing the packaged items to a carrier for delivery, and delivering the items. Even for small items or small numbers of items, boxes or other packages are transported by relatively large vehicles over roads, sometimes across long distances.
One alternative to road-based delivery is to deliver packages through the air using an unmanned aerial vehicle (UAV). As package delivery by a UAV becomes more common, delivery by a UAV presents many challenges and design considerations. For example, it may not always be possible to land a UAV to deliver a package, and it may not always be possible to drop a package to the ground from a particular height above the ground.